The kiosk at the entrance warns of open mine shafts. Most that we could see had grates over the top. They make for great views straight down the shafts!
Several other shafts extend into the earth surrounding the primary mine.
Ruins of the former city are everywhere!
The smelter towers above while Big-E makes his way toward it.
Sign below the smelter.
It's an impressive sight. Unfortunately shooters have blasted a lot of it away.
Wikipedia has an article that explains the Reverberatory Furnace